1. Field of the Invention
The present invention relates to an inductorless ballast. More specifically, the present invention relates to an inductorless ballast for a fluorescent light.
2. Description of the Prior Art
Existing solutions for driving a fluorescent lamp at high-frequency include some form of current limiting, or "ballast," between the high-frequency voltage source (usually a pair of transistors arranged in a half-bridge circuit) and the lamp. The ballast may be a resistor (when driving the lamp at D.C.) or an inductor or capacitor (when driving the lamp at high-frequency). These passive components provide a frequency dependent impedance for current limiting and provide smooth, quasi-sinusoidal lamp voltage and current waveforms. The frequency of operation of the ballast is much higher than the ionization time constant of the lamp, therefore eliminating any re-strike during each cycle of lamp voltage.
Conventional ballasts for fluorescent lamps, which typically incorporate an inductor for driving the lamp at high-frequency, are bulky, heavy and unreliable. It would be desirable to provide an inductorless ballast for high frequency fluorescent lamp operation which does not have the above-mentioned disadvantages.